Editing Montreal Protocol (section)

== Terms and purposes ==
The treaty<ref group="Notes">The full terms of the Montreal Protocol are available from the [http://ozone.unep.org/Publications/MP_Handbook/Section_1.1_The_Montreal_Protocol/ United Nations Environment Programme (UNEP) Ozone Secretariat] {{Webarchive|url=https://web.archive.org/web/20080703062032/http://ozone.unep.org/Publications/MP_Handbook/Section_1.1_The_Montreal_Protocol/ |date=3 July 2008 }}</ref> is structured around several groups of [[halogenated hydrocarbon]]s that lead to the catalytic destruction of stratospheric ozone. All of the ozone depleting substances controlled by the Montreal Protocol contain either [[chlorine]] or [[bromine]] (substances containing only [[fluorine]] do not harm the ozone layer, although they can be strong greenhouse gases). Some ozone-depleting substances (ODSs) are not yet controlled by the Montreal Protocol, including [[nitrous oxide]] (N<sub>2</sub>O). For a table of ozone-depleting substances controlled by the Montreal Protocol see:<ref>{{cite web |url=http://www.epa.gov/ozone/ods.html |title=Class I Ozone-depleting Substances &#124; Science &#124; Ozone Layer Protection &#124; US EPA |publisher=Epa.gov |date=2013-02-15 |access-date=28 October 2006 |archive-date=11 May 2008 |archive-url=https://web.archive.org/web/20080511181352/http://www.epa.gov/ozone/ods.html |url-status=dead }}</ref>

For each group of ODSs, the treaty provides a timetable on which the production of those substances must be reduced and eventually eliminated. This includes a 10-year phase-out for developing countries<ref>An Interview with Lee Thomas, EPA’s 6th Administrator. [http://www.epaalumni.org/history/video/interview.cfm?id=28 Video] {{Webarchive|url=https://web.archive.org/web/20200922211841/https://www.epaalumni.org/history/video/interview.cfm?id=28 |date=22 September 2020 }}, [https://www.epaalumni.org/userdata/pdf/60740780F5ACB3D5.pdf#page=1 Transcript] {{Webarchive|url=https://web.archive.org/web/20190412070306/https://www.epaalumni.org/userdata/pdf/60740780F5ACB3D5.pdf#page=1 |date=12 April 2019 }} (see p15). 19 April 2012.</ref> identified in Article 5 of the treaty.

=== Chlorofluorocarbons (CFCs) Phase-out Management Plan ===

The purpose of the treaty is that each signatory states:

{{blockquote|Recognizing that worldwide emissions of certain substances can significantly deplete and otherwise modify the ozone layer in a manner that is likely to result in adverse effects on human health and the environment.  Determined to protect the ozone layer by taking precautionary measures to control equitably total global emissions of substances that deplete it with the ultimate objective of their elimination on the basis of developments in scientific knowledge

Acknowledging that special provision is required to meet the needs of developing countries

shall accept a series of stepped limits on [[Chlorofluorocarbon|CFC]] use and production, including:

{{block indent|<!-- Needed for indent on mobile -->{{plainlist|
* from 1991 to 1992 its levels of consumption and production of the controlled substances in Group I of Annex A do not exceed 150 percent of its calculated levels of production and consumption of those substances in 1986;
* from 1994 its calculated level of consumption and production of the controlled substances in Group I of Annex A does not exceed, annually, twenty-five percent of its calculated level of consumption and production in 1986.
* from 1996 its calculated level of consumption and production of the controlled substances in Group I of Annex A does not exceed zero.}}}}}}

There was a faster phase-out of halon-1211, -2402, -1301, There was a slower phase-out (to zero by 2010) of other substances (halon 1211, 1301, 2402; CFCs 13, 111, 112, etc.){{Contradictory inline|date=January 2017}} and some chemicals were given individual attention ([[Carbon tetrachloride]]; [[1,1,1-Trichloroethane|1,1,1-trichloroethane]]). The phasing-out of the less damaging [[HCFC]]s only began in 1996 and will go on until a complete phasing-out is achieved by 2030.

There were a few exceptions for "essential uses" where no acceptable substitutes were initially found (for example, metered dose inhalers commonly used to treat asthma and chronic obstructive pulmonary disease were previously exempt) or [[Halomethane|Halon]] fire suppression systems used in submarines and aircraft (but not in general industry).

The substances in Group I of Annex A are:

* CFCl<sub>3</sub> ([[Trichlorofluoromethane|CFC-11]])
* CF<sub>2</sub>Cl<sub>2</sub> ([[Dichlorodifluoromethane|CFC-12]])
* C<sub>2</sub>F<sub>3</sub>Cl<sub>3</sub> ([[CFC-113]])
* C<sub>2</sub>F<sub>4</sub>Cl<sub>2</sub>([[CFC-114]])
* C<sub>2</sub>F<sub>5</sub>Cl ([[CFC-115]])

The provisions of the Protocol include the requirement that the Parties to the Protocol base their future decisions on the current scientific, environmental, technical, and economic information that is assessed through panels drawn from the worldwide expert communities. To provide that input to the decision-making process, advances in understanding on these topics were assessed in 1989, 1991, 1994, 1998 and 2002 in a series of reports entitled [[Scientific assessment of ozone depletion]], by the Scientific Assessment Panel (SAP).<ref>{{Cite web|url=http://ozone.unep.org/en/assessment-panels/scientific-assessment-panel|title=Scientific Assessment Panel {{!}} OZONE SECRETARIAT|website=ozone.unep.org|language=en|access-date=2018-04-23|archive-url=https://web.archive.org/web/20180424202422/http://ozone.unep.org/en/assessment-panels/scientific-assessment-panel|archive-date=24 April 2018|url-status=dead}}</ref>

In 1990 a Technology and Economic Assessment Panel was also established as the technology and economics advisory body to the Montreal Protocol Parties.<ref>{{Cite web|url=http://ozone.unep.org/en/assessment-panels/technology-and-economic-assessment-panel|title=Technology and Economic Assessment Panel {{!}} OZONE SECRETARIAT|website=ozone.unep.org|language=en|access-date=2018-04-23|archive-url=https://web.archive.org/web/20180126070701/http://ozone.unep.org/en/assessment-panels/technology-and-economic-assessment-panel|archive-date=26 January 2018|url-status=dead}}</ref> The Technology and Economic Assessment Panel (TEAP) provides, at the request of Parties, technical information related to the alternative technologies that have been investigated and employed to make it possible to virtually eliminate use of Ozone Depleting Substances (such as CFCs and Halons), that harm the ozone layer. The TEAP is also tasked by the Parties every year to assess and evaluate various technical issues including evaluating nominations for essential use exemptions for CFCs and halons, and nominations for critical use exemptions for methyl bromide. TEAP's annual reports are a basis for the Parties' informed decision-making.

Numerous reports have been published by various inter-governmental, governmental and non-governmental organizations to catalogue and assess alternatives to the ozone depleting substances, since the substances have been used in various technical sectors, like in refrigeration, air conditioning, flexible and rigid foam, fire protection, aerospace, electronics, agriculture, and laboratory measurements.<ref>Use of ozone depleting substances in laboratories. TemaNord 2003:516. http://norden.diva-portal.org/smash/get/diva2:796602/FULLTEXT01.pdf {{Webarchive|url=https://web.archive.org/web/20151121220053/http://norden.diva-portal.org/smash/get/diva2:796602/FULLTEXT01.pdf |date=21 November 2015 }}</ref><ref>The Technical and Economic Feasibility of Replacing Methyl Bromide in Developing Countries. Friends of the Earth, Washington, 173 pp, 1996</ref><ref>Guidance on the DOE Facility Phaseout of Ozone-Depleting Substances. 1995. {{cite web |url=http://homer.ornl.gov/nuclearsafety/nsea/oepa/guidance/ozone/phaseout.pdf |title=Guidance on the DOE Facility Phaseout of Ozone-Depleting Substances |access-date=2007-12-03 |url-status=dead |archive-url=https://web.archive.org/web/20080227052411/http://homer.ornl.gov/nuclearsafety/nsea/oepa/guidance/ozone/phaseout.pdf |archive-date=27 February 2008 }}</ref>

=== Hydrochlorofluorocarbons (HCFCs) Phase-out Management Plan (HPMP) ===
Under the Montreal Protocol on Substances that Deplete the Ozone Layer, especially Executive Committee (ExCom) 53/37 and ExCom 54/39, Parties to this Protocol agreed to set year 2013 as the time to freeze the consumption and production of HCFCs for developing countries. For developed countries, reduction of HCFC consumption and production began in 2004 and 2010, respectively, with 100% reduction set for 2020.  Developing countries agreed to start reducing its consumption and production of HCFCs by 2015, with 100% reduction set for 2030.<ref>{{Cite web|url=https://ozone.unep.org/montreal-protocol-substances-deplete-ozone-layer/32506|title=The Montreal Protocol on Substances that Deplete the Ozone Layer|website=United Nations Environment Programme|access-date=16 November 2018|archive-date=14 October 2018|archive-url=https://web.archive.org/web/20181014170949/http://ozone.unep.org/montreal-protocol-substances-deplete-ozone-layer/32506|url-status=dead}}</ref>

Hydrochlorofluorocarbons, commonly known as HCFCs, are a group of human-made compounds containing hydrogen, chlorine, fluorine and carbon. They are not found anywhere in nature. HCFC production began to take off after countries agreed to phase out the use of CFCs in the 1980s, which were found to be destroying the ozone layer. Like CFCs, HCFCs are used for refrigeration, aerosol propellants, foam manufacture and air conditioning. Unlike the CFCs, however, most HCFCs are broken down in the lowest part of the atmosphere and pose a much smaller risk to the ozone layer. Nevertheless, HCFCs are very potent [[greenhouse gas]]es, despite their very low atmospheric concentrations, measured in parts per trillion (million million).

The HCFCs are transitional CFCs replacements, used as [[refrigerant]]s, solvents, blowing agents for plastic foam manufacture, and fire extinguishers. In terms of [[ozone depletion potential]] (ODP), in comparison to CFCs that have ODP 0.6–1.0, these HCFCs have lower ODPs (0.01–0.5). In terms of [[global warming potential]] (GWP), in comparison to CFCs that have GWP 4,680–10,720, HCFCs have lower GWPs (76–2,270).{{Citation needed|date=September 2024}}

=== Hydrofluorocarbons (HFCs) ===

On 1 January 2019, the [[Kigali Amendment]] to the Montreal Protocol came into force.<ref>{{Cite web|url=https://ozone.unep.org/ozone-timeline|website=ozone.unep.org|access-date=2020-04-22|title=Ozone Timeline &#124; Ozone Secretariat }}</ref> Under the Kigali Amendment countries promised to reduce the use of hydrofluorocarbons (HFCs) by more than 80% over the next 30 years.<ref>{{Cite web|url=https://www.standardmedia.co.ke/article/2001308090/kigali-amendment-heralds-new-dawn-for-climate-change-action|title=Kigali Amendment heralds new dawn for climate change action|last=Msuya|first=Joyce|website=The Standard|language=en|access-date=2020-04-22}}</ref> By 27 December 2018, 65 countries had ratified the Amendment.<ref name="standardmedia_Msuya_20190102">{{Cite web| last = Msuya| first = Joyce | title = Kigali Amendment heralds new dawn for climate change action| work = The Standard| access-date=2 January 2019| url = https://www.standardmedia.co.ke/article/2001308090/kigali-amendment-heralds-new-dawn-for-climate-change-action |date=2 January 2019}}</ref> {{As of|2024|October|31}}, 160 states<ref name="UNTC">{{cite web |title=Amendment to the Montreal Protocol on Substances that Deplete the Ozone Layer |url=https://treaties.un.org/Pages/ViewDetails.aspx?src=IND&mtdsg_no=XXVII-2-f&chapter=27 |access-date=October 31, 2024 |website=United Nations Treaty Collective}}</ref> and the [[European Union]]<ref>{{Cite web |date=July 14, 2020 |title=Kigali Amendment hits milestone 100th ratification, boosting climate action |url=http://www.unep.org/news-and-stories/press-release/kigali-amendment-hits-milestone-100th-ratification-boosting-climate |url-status=live |archive-url=https://web.archive.org/web/20221103062228/http://www.unep.org/news-and-stories/press-release/kigali-amendment-hits-milestone-100th-ratification-boosting-climate |archive-date=November 3, 2022 |access-date=September 20, 2022 |website=[[United Nations Environment Programme]]}}</ref> have ratified the Amendment.

Produced mostly in developed countries, [[Organofluorine chemistry#Hydrofluorocarbons|hydrofluorocarbons]] (HFCs) replaced CFCs and HCFCs. HFCs pose no harm to the ozone layer because, unlike CFCs and HCFCs, they do not contain chlorine. They are, however, greenhouse gases, with a high global warming potential (GWP), comparable to that of CFCs and HCFCs.<ref>{{cite web |url=http://www.downtoearth.org.in/content/climate-irrationality |title=Climate of irrationality |publisher=Down To Earth |date=18 September 2012 |access-date=28 September 2012 |archive-date=1 October 2012 |archive-url=https://web.archive.org/web/20121001022841/http://www.downtoearth.org.in/content/climate-irrationality |url-status=dead }}</ref><ref>{{Cite web|url=https://www.canada.ca/en/environment-climate-change/services/air-pollution/issues/ozone-layer/depletion-impacts/substances.html#fn2|title=Ozone-depleting substances|last=Canada|first=Environment and Climate Change|date=2008-12-02|website=aem|access-date=2020-04-22}}</ref> In 2009, a study calculated that a fast phasedown of high-GWP HFCs could potentially prevent the equivalent of up to 8.8 Gt {{CO2}}-eq per year in emissions by 2050.<ref>{{cite journal | vauthors = Velders GJ, Fahey DW, Daniel JS, McFarland M, Andersen SO | title = The large contribution of projected HFC emissions to future climate forcing | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 106 | issue = 27 | pages = 10949–54 | date = July 2009 | pmid = 19549868 | pmc = 2700150 | doi = 10.1073/pnas.0902817106 | bibcode = 2009PNAS..10610949V | doi-access = free }}</ref> A proposed phasedown of HFCs was hence projected to avoid up to 0.5C of warming by 2100 under the high-HFC growth scenario, and up to 0.35C under the low-HFC growth scenario.<ref>{{Cite journal|url=https://www.researchgate.net/publication/260830030|title=The role of HFCs in mitigating 21st century climate change|last1=Xu|first1=Yangyang|last2=Zaelke|first2=Durwood|last3=Velders|first3=Guus J. M.|last4=Ramanathan|first4=V|journal=Atmospheric Chemistry & Physics |date=2013-06-01|volume=13|issue=12 |page=6083 |doi=10.5194/acp-13-6083-2013 |doi-access=free |bibcode=2013ACP....13.6083X }}</ref> Recognizing the opportunity presented for fast and effective phasing down of HFCs through the Montreal Protocol, starting in 2009 the [[Federated States of Micronesia]] proposed an amendment to phase down high-GWP HFCs,<ref>{{Cite web|url=http://ozone.unep.org/Meeting_Documents/oewg/29oewg/OEWG-29-8E.pdf|title=Proposed amendment to the Montreal Protocol|date=4 May 2009|website=United Nations Environment Programme|access-date=17 May 2018}}</ref> with the U.S., Canada, and Mexico following with a similar proposal in 2010.<ref>{{Cite web|url=http://ozone.unep.org/Meeting_Documents/mop/22mop/MOP-22-5E.pdf|title=Proposed amendment to the Montreal Protocol|website=United Nations Environment Programme|date=30 July 2010|access-date=17 May 2018}}</ref>

After seven years of negotiations, in October 2016 at the 28th Meeting of the Parties to the Montreal Protocol in [[Kigali]], the Parties to the Montreal Protocol adopted the Kigali Amendment whereby the Parties agreed to phase down HFCs under the Montreal Protocol.<ref>{{Cite web|url=http://conf.montreal-protocol.org/meeting/mop/mop-28/final-report/English/MOP-28-12E.pdf|title=Report of the Twenty-Eighth Meeting of the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer|date=October 2016|access-date=25 January 2018|archive-date=26 January 2018|archive-url=https://web.archive.org/web/20180126012702/http://conf.montreal-protocol.org/meeting/mop/mop-28/final-report/English/MOP-28-12E.pdf|url-status=dead}}</ref> The amendment to the Montreal Protocol commits the signatory parties to reduce  their HFC production and consumption by at least 85 per cent from the annual average value in the period from 2011 to 2013. A group of developing countries including China, Brazil and South Africa are mandated to reduce their HFC use by 85 per cent of their average value in 2020-22 by the year 2045. India and some other developing countries – Iran, Iraq, Pakistan, and some oil economies like Saudi Arabia and Kuwait – will cut down their HFCs by 85 per cent of their values in 2024-26 by the year 2047.

On 17 November 2017, ahead of the 29th Meeting of the Parties of the Montreal Protocol, Sweden became the 20th Party to ratify the Kigali Amendment, pushing the Amendment over its ratification threshold ensuring that the Amendment would enter into force 1 January 2019.<ref>{{Cite news|url=https://www.unenvironment.org/news-and-stories/press-release/montreal-protocol-celebrates-another-milestone-agreement-reduce|title=Montreal Protocol celebrates another milestone as agreement to reduce climate-warming gases is set to enter into force in 2019|work=UN Environment|access-date=2018-01-25|language=en}}</ref>